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A207758 Number of nX4 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 0 1 vertically.

%I A207758 #7 Jul 22 2025 20:48:12
%S A207758 9,81,221,663,2245,6459,17563,48649,131269,344873,902075,2342619,
%T A207758 6021103,15395621,39219821,99470227,251449497,634148313,1595707571,
%U A207758 4007571389,10049914241,25169768531,62965428327,157368593823,392995561393
%N A207758 Number of nX4 0..1 arrays avoiding 0 0 0 and 1 0 1 horizontally and 0 1 1 and 1 0 1 vertically.
%C A207758 Column 4 of A207762
%H A207758 R. H. Hardin, <a href="/A207758/b207758.txt">Table of n, a(n) for n = 1..210</a>
%F A207758 Empirical: a(n) = 6*a(n-1) -14*a(n-2) +30*a(n-3) -77*a(n-4) +120*a(n-5) -153*a(n-6) +281*a(n-7) -311*a(n-8) +236*a(n-9) -422*a(n-10) +351*a(n-11) -110*a(n-12) +387*a(n-13) -284*a(n-14) -3*a(n-15) -264*a(n-16) +172*a(n-17) +52*a(n-18) +84*a(n-19) -56*a(n-20) -24*a(n-21) -16*a(n-22) +16*a(n-23) for n>24
%e A207758 Some solutions for n=4
%e A207758 ..1..1..0..0....0..0..1..1....1..1..0..0....0..0..1..1....1..1..0..0
%e A207758 ..0..1..0..0....1..1..1..0....0..1..1..0....0..0..1..1....0..1..1..0
%e A207758 ..0..1..1..0....0..0..1..0....0..1..0..0....0..1..1..0....0..1..0..0
%e A207758 ..1..1..0..0....0..0..1..1....1..1..0..0....0..0..1..0....0..1..0..0
%K A207758 nonn
%O A207758 1,1
%A A207758 _R. H. Hardin_ Feb 19 2012